How To Grow Salt Crystals

I was asked once why I have so many holiday themed activities. We do have tons thats for sure. But you know what? The holidays are magical for young kids. So my questions is why not do holiday themed science activities? You can make slime, grow crystals, build structures, and so much more. This is the exact reason why we have written about how to grow salt crystals for this fun and engaging Easter science activity.

GROW SALT CRYSTALS FOR SIMPLE SCIENCE EXPERIMENT FOR PRESCHOOL!

GROWING CRYSTALS

Every time we grow a new batch of crystals, whether they are salt crystals or borax crystals, we are always amazed by how cool this type of science experiment is to do! Not to mention how easy it is as well!

There are a few ways you can explore how to grow crystals that we are starting to experiment with more and more this year. We have always grown the traditional borax crystals on pipe cleaners type, but we are having fun with learning how to grow salt crystals too.

REPEATING SCIENCE ACTIVITIES FOR BETTER UNDERSTANDING

I have noticed that young kids do very well with repetition, but repetition doesn’t have to be boring. We love to share hands-on science activities that are always fun and exciting but also repeat the same concepts to develop understanding for young learners.

That’s where holiday science activities come in to play! We have now done a bunch of different holiday themed salt crystals activities like snowflakes, hearts, and gingerbread men. Doing it this way gives us more chances to practice what we have already learned about but with variety!

HOW TO GROW SALT CRYSTALS

Learning how to grow salt crystals is a great alternative for young kids who may still be into tasting their science activities. It also allows them to be much more hands-on and participate in the set up of the activity. However, borax crystals should also be made under close adult supervision and are not taste friendly.

Looking for easy to print activities, and inexpensive problem-based challenges?

We have you covered…

Click below to get your quick and easy STEM challenges.

YOU WILL NEED:

Construction Paper

Water

Salt

Container and Spoon {for mixing salt solution}

Tray or Plate

Egg Shape {for tracing}, Scissors, Pencil

Hole Puncher and String {optional if you want to hang them when you are finished}

SALT CRYSTALS SET UP

STEP 1: Start by making as many egg shaped cut outs as you would like. Or you can just make one giant egg if you prefer that fills your tray. You will want the shapes to lay as flat as possible, so we used a cookie tray.

At this point, go ahead and punch a hole in the top of the egg cutout if you plan to use your salt crystal eggs as an ornament!

MAKING A SUPER SATURATED SOLUTION FOR GROWING SALT CRYSTALS

First you need to start with hot water, so this is an adult only step if needed. We microwaved about 2 cups of water for 2 minutes. Though you can see from the above right photo, we did not use all of our solution for our tray.

Now, it’s time to add the salt. We added one tablespoon at a time, stirring very well until completely dissolved. You can feel the point at which it’s not gritty as you stir. {Close to 6 tablespoons for us}

Do this with each tablespoon until you can’t get rid of that gritty feeling. You will see a bit of salt on the bottom of the container. This is your super saturated solution!

WHAT IS A SUPERSATURATED SOLUTION?

A supersaturated solution is a mixture that can’t hold any more particles. Like with the salt here, we have filled all the space in the water with salt and the rest is left behind.

Water molecules are close together in cold water, but when you heat the water up, the molecules spread away from each other. This is what allows you to dissolve more salt in the water than you normally could. It even appears cloudy.

You can try this experiment with cold water to compare the differences in the amount of salt needed to get this mixture, and you can compare the results of the crystals afterward.

BEFORE you pour the solution, move your tray to a quiet location that won’t be disturbed. It’s easier than trying to do it after you have added the liquid. We know!

Go ahead and pour your mixture over the eggs just covering them with a thin layer of the solution.

You can see that our egg cutouts had a bit of a tough time staying separated and we didn’t try to fix it too much. You could experiment with different methods like tape to stick them down first or an object to block their movement.

Now you just need to give your eggs time to form the salt crystals. We set this up mid-morning and started seeing results by late evening and definitely the next day. Plan to allow approximately 3 days for this activity. Once the water has evaporated, they will be ready.

Borax Crystals are ready faster if you need a quicker crystal growing activity!!

We transfer our salt crystal covered egg cutouts to paper towels and let them dry out for awhile. Plus the crystals really seem to bond nicely as everything dries out more.

When they are nice and dry, add a string if you wish. Examine the salt crystals with a magnifying glass too. You can explore one single crystal as well like we did below.

Looking for easy to print activities, and inexpensive problem-based challenges?

We have you covered…

Click below to get your quick and easy STEM challenges.

These crystals are so cool and they will always be cubed shaped whether they are by themselves or in a cluster. This is because a crystal is made of molecules that come together in a repeating pattern. Check out our single crystal above!

HOW DO SALT CRYSTALS FORM

You have already learned a bit about a supersaturated solution and how it’s made and you have also learned that a crystal is made up of molecules that will form a specific pattern if properly grown.

So how do the salt crystals grow? As the solution cools the water molecules start to come back together, the particles of salt in the solution fall out of place and onto the paper. More will connect with the molecules that have already fallen out of the solution.

As the salt solution cools and the water evaporates, the atoms (niacin and chlorine) are no longer separated by water molecules. They begin to bond together and then bond further forming the special cube-shaped crystal for salt.

THE CRUCIAL FACTOR: WATER TEMPERATURE

In order to grow the best crystals, the solution has to cool slowly. This allows any impurities that are also caught up in the solution to be rejected by the forming crystals. Remember the crystal molecules are all the same and are looking for more of the same!

If the water cools too quickly the impurities are trapped creating an unstable, misshapen crystal. You can see that here when we tried to use different containers for our borax crystals. One container cooled slowly and one container cooled quickly.

SALT CRYSTALS SCIENCE PROJECT

This salt crystals experiment would make an easy science fair project. You could experiment with different water temperatures, different trays or plates, or covering the crystals slightly to minimize heat loss.

You could also vary the type of salt used. What happens to drying time or crystal formation if you use rock salt or Epsom salt?

A science project like our how to grow salt crystals Easter science activity is a wonderful way to encourage a love of the sciences for years to come. These activities may seem simple but there is so much to share with your kids even if you are just touching on the basics when you are experimenting together.

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